The Congo and the Timneh are totally different subspecies. The pic you have is of two Timneh Greys. Their beaks are a dead giveaway as Timnehs have that fleshy color while Congos are totally black. They are also darker than Congos and have maroon tails instead of red.
I think it's too timneh. because its characteristics are timneh completed. but my friend said it's because of variations congo. so I need a precise advice
We have had Timneh Greys for most of my life in the family, and those are for sure Timneh greys . Interesting observation, most pet Timneh Greys tend to be lighter than Parent Raised or breeder Birds kept in Aviaries, some pet T's even seem slightly smaller than Aviary Birds.... Maybe its just imagination though lol...But those Deffinately Timnehs